Belted vehicular restraint systems commonly utilize ratcheting belt retractors which lock the belt to restrain the vehicle occupant when a motion sensitive element in the retractor experiences acceleration in excess of a predetermined threshold. The retractors may be mounted on the vehicle body or in the vehicle door, depending on the installation.
In one type of restraint system, one or more of the retractors are mounted in the vehicle door and the belts are adapted to be continuously coupled to provide a passive (automatic) restraint system. In such a system, the door-mounted retractors tend to lock the belts around the occupant in response to sudden open or closure of the vehicle door. To overcome this inconvenience, systems of this type commonly include an electrically or mechanically activated mechanism which desensitizes the motion sensitive element of the retractor when the vehicle door is opened. See, for example, the U.S. Pat. No. Compeau et al. 4,598,932 and Arlauskas et al. U.S. Pat. No. 3,692,328, both assigned to the assignee of the present invention.